Molecular Cloning and Function Analysis of an Anthocyanidin Synthase Gene from Ginkgo biloba, and Its Expression in Abiotic Stress Responses

Feng Xu,Hua Cheng,Rong Cai,Lin Ling Li,Jie Chang,Jun Zhu,Feng Xia Zhang,Liu Ji Chen,Yan Wang,Shu Han Cheng,Shui Yuan Cheng 한국분자세포생물학회 2008 Molecules and cells Vol.26 No.6

Anthocyanidin synthase (ANS, leucoanthocyanidin oxygenase), a 2-oxoglutarate iron-dependent oxygenase, catalyzed the penultimate step in the biosynthesis of the anthocyanin class of flavonoids, from the colorless leucoanthocyanidins to the colored anthocyanidins. The full-length cDNA and genomic DNA sequences of ANS gene (designated as GbANS) were isolated from Ginkgo biloba for the first time. The full-length cDNA of GbANS contained a 1062-bp open reading frame (ORF) encoding a 354-amino-acid protein. The genomic DNA analysis showed that GbANS gene had three exons and two introns. The deduced GbANS protein showed high identities to other plant ANSs. The conserved amino acids (H-X-D) ligating ferrous iron and residues (R-X-S) participating in 2-oxoglutarate binding were found in GbANS at the similar positions like other ANSs. Southern blot analysis indicated that GbANS belonged to a multi-gene family. The expression analysis by real-time PCR showed that GbANS expressed in a tissue-specific manner in G. biloba. GbANS was also found to be up-regulated by all of the six tested abiotic stresses, UV-B, abscisic acid, sucrose, salicylic acid, cold and ethylene, consistent with the promoter region analysis of GbANS. The recombinant protein was successfully expressed in E. coli strain with pET-28a vector. The in vitro enzyme activity assay by HPLC indicated that recombinant GbANS protein could catalyze the formation the cyanidin from leucocyanidin and conversion of dihydroquercetin to quercetin, suggesting GbANS is a bifunctional enzyme within the anthocyanidin and flavonol biosynthetic pathway.

Inter regional diffusion of policy innovation in China A comparative case study

Xu-Feng Zhu 서울대학교행정대학원 2017 Asian Journal of Political Science Vol.25 No.3

Classic theoretical research on the diffusion of policy innovation is usually based on decentralized democratic regimes. However, in authoritarian centralized countries such as China, questions such as, ‘What are the driving forces and the structural dynamics behind local government policy innovation and inter-regional diffusion?’ and ‘How do the governmental structural factors lead to the different patterns of diffusion of policy innovation across local governments?’ are interesting research topics. The theoretical framework proposed in this study highlights the roles of the contingent vertical and horizontal governmental relations in innovation diffusion. I extract two key properties: vertical mandatory intervention from the central government and horizontal political competition among peer governments. This research uses four models to develop a new typology of the interregional diffusion of policy innovation in China: (1) the enlightenment model, (2) the championship model, (3) the designation model, and (4) the recognition model. A comparative case study is conducted in this research, with four policy cases showing that China has developed diversified mechanisms to encourage local governments to perform policy innovation and inter-regional diffusion.

Triterpenoid saponins from Clinopodium chinense (Benth.) O. Kuntze and their biological activity

Yin-Di Zhu,Jing-Yi Hong,Feng-Da Bao,Na Xing,Ling-Tian Wang,Zhong-Hao Sun,Yun Luo,Hai Jiang,Xudong Xu,Nai-Liang Zhu,Hai-Feng Wu,Gui-Bo Sun,Jun-Shan Yang 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.12

Four new ursane-type triterpenoid saponins, clinopoursaponins A–D (1–4), six new oleanane-type triterpenoid saponins, clinopodiside VII–XII (5–10), as well as eight known triterpene analogues (11–18), were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. The structures of the new compounds were determined based on extensive spectral analyses, including 1D (1H and 13C) and 2D NMR experiments (COSY, NOESY, HSQC, 2D TOCSY, HSQC-TOCSY and HMBC), HR-ESI-MS and chemical methods. Compounds 1–18 were evaluated for their protective effects against anoxia/reoxygenation-induced apoptosis in H9c2 cells and cytotoxicities against murine mammary carcinoma cell line 4T1. Compounds 8, 9 and 18 exhibited significant protective effects, while compound 1 exhibited cytotoxic activity with IC50 value of 7.4 μm compared to 7.6 μm for the positive control 10-hydroxycamptothecin.

The Effects of ASMase Mediated Endothelial Cell Apoptosis in Multiple Hypofractionated Irradiations in CT26 Tumor Bearing Mice

Zhu, Hong,Deng, Kai,Zhao, Ya-Qin,Wang, Xin,Shen, Ya-Li,Liu, Tai-Guo,Cui, Dan-Dan,Xu, Feng Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: To investigate the effects of ASMase mediated endothelial cell apoptosis in multiple hypofractionated irradiations in CT26 tumor bearing mice. Materials and Methods: Thirty-five CT26 tumor bearing mice were subjected to single ionizing radiation (IR) of 0, 3, 6, 9, 12, 15, 18 Gy. Eight hours after IR, the mice were sacrificed and tumor tissues were used for CD31 immunohistochemistry staining, TUNEL and CD31 double staining, ASMase activity assay. Then 6 and 12 Gy were chosen for multiple hypofractionated IR experiments according to the above results. Each time after IR, 5 mice were sacrificed and assayed as above. Results: The ASMase activities were increased significantly after a single IR of 12 Gy or higher which was accompanied with remarkable increased endothelial cell apoptosis and decreased MVD. For 6 Gy which was not high enough to trigger ASMase activation, after 2 or more times of IR, the ASMase activities were significantly increased accompanied with remarkable increased endothelial cell apoptosis and decreased MVD. While for 12 Gy, after 2 or more times of IR, the ASMase activities and endothelial cell apoptosis rates were maintained without remarkable increase; however, the MVD was significantly decreased. What's more, the cancer cell apoptosis rates were significantly increased after multiple IR for both 6 Gy and 12 Gy. Conclusions: ASMase mediated endothelial cell apoptosis may play an important role in the process of multiple hypofractionated IR for CT26 colorectal carcinoma.

Rice Gene OsDSR-1 Promotes Lateral Root Development in Arabidopsis Under High-Potassium Conditions

Xu Ming Yin,Pedro S. C. F. Rocha,Man Ling Wang,Yu Xin Zhu,Luo Ye Li,Shu Feng Song,Xinjie Xia 한국식물학회 2011 Journal of Plant Biology Vol.54 No.3

Rice gene Oryza sativa Drought Stress Response-1 (OsDSR-1) was one of the genes identified to be responsive to drought stress in the panicle of rice at booting and heading stages by both microarray and quantitative real-time PCR analyses. OsDSR-1 encodes a putative calcium-binding protein, and its overexpression in Arabidopsis rendered transgenic plants to produce much shorter lateral roots (LRs) than wild-type (WT) plants in the medium supplemented with abscisic acid (ABA), suggesting that OsDSR-1 may act as a positive regulator during the process of ABA inhibition of LR development. No significant difference was observed in the total LR length between WT and transgenic plants in the media with the increase of only osmotic stress caused by NaCl, LiCl, and mannitol, while transgenic Arabidopsis seedlings appeared to produce larger root systems with longer total LR lengths under highpotassium conditions than WT seedlings. Further analysis showed that external Ca^2+ was required for the production of larger root systems, indicating that the promotion by OsDSR-1 of the LR development of transgenic Arabidopsis seemed to occur in a Ca^2+ -dependent manner under high-potassium conditions. We propose that OsDSR-1 may function as a calcium sensor of the signal transduction pathway controlling the LR development under high-potassium conditions.

Aberrant Expression of CCAT1 Regulated by c-Myc Predicts the Prognosis of Hepatocellular Carcinoma

Zhu, Hua-Qiang,Zhou, Xu,Chang, Hong,Li, Hong-Guang,Liu, Fang-Feng,Ma, Chao-Qun,Lu, Jun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: CCAT1 has been reported to be linked with pathogenesis of malignancies including colon cancer and gastric cancer. However, the regulatory effect of CCAT1 in hepatocellular carcinoma (HCC) remains unclear. The purpose of this research was to identify any role of CCAT1 in the progression of HCC. Materials and Methods: Real time-PCR was performed to test the relative expression of CCAT1 in HCC tissues. A computation screen of CCAT1 promoter was conducted to search for transcription-factor-binding sites. The association of c-Myc with CCAT1 promoter in vivo was tested by Pearson correlation analysis and chromatin immunoprecipitation assay. Additionally, Kaplan-Meier analysis and Cox proportional hazards analyses were performed. Results: c-Myc directly binds to the E-box element in the promoter region of CCAT, and when ectopically expressed increases promoter activity and expression of CCAT1. Moreover, Kaplan-Meier analysis demonstrated that the patients with low expression of CCAT1 demonstrated better overall and relapse-free survival compared with the high expression group. Cox proportional hazards analyses showed that CCAT1 expression was an independent prognostic factor for HCC patients. Conclusions: The findings demonstrated CCAT1, acting as a potential biomarker in predicting the prognosis of HCC, is regulated by c-Myc.

Long Noncoding RNA HOXA11-AS Modulates the Resistance of Nasopharyngeal Carcinoma Cells to Cisplatin via miR-454-3p/c-Met

Feng-Jie Lin,Xian-Dong Lin,Lu-Ying Xu,Shi-Quan Zhu 한국분자세포생물학회 2020 Molecules and cells Vol.43 No.10

To elucidate the mechanism of action of HOXA11-AS in modulating the cisplatin resistance of nasopharyngeal carcinoma (NPC) cells. HOXA11-AS and miR-454-3p expression in NPC tissue and cisplatin-resistant NPC cells were measured via quantitative reverse transcriptase polymerase chain reaction. NPC parental cells (C666-1 and HNE1) and cisplatin-resistant cells (C666-1/DDP and HNE1/DDP) were transfected and divided into different groups, after which the MTT method was used to determine the inhibitory concentration 50 (IC50) of cells treated with different concentrations of cisplatin. Additionally, a clone formation assay, flow cytometry and Western blotting were used to detect DDP-induced changes. Thereafter, xenograft mouse models were constructed to verify the in vitro results. Obviously elevated HOXA11-AS and reduced miR-454-3p were found in NPC tissue and cisplatin-resistant NPC cells. Compared to the control cells, cells in the si-HOXA11-AS group showed sharp decreases in cell viability and IC50, and these results were reversed in the miR-454-3p inhibitor group. Furthermore, HOXA11-AS targeted miR-454-3p, which further targeted c-Met. In comparison with cells in the control group, HNE1/DDP and C666-1/DDP cells in the si-HOXA11-AS group demonstrated fewer colonies, with an increase in the apoptotic rate, while the expression levels of c-Met, p-Akt/Akt and p-mTOR/mTOR decreased. Moreover, the si-HOXA11-AS-induced enhancement in sensitivity to cisplatin was abolished by miR-454-3p inhibitor transfection. The in vivo experiment showed that DDP in combination with si-HOXA11-AS treatment could inhibit the growth of xenograft tumors. Silencing HOXA11-AS can inhibit the c-Met/AKT/mTOR pathway by specifically upregulating miR-454-3p, thus promoting cell apoptosis and enhancing the sensitivity of cisplatin-resistant NPC cells to cisplatin.

Characterization of an inhibitor of apoptosis gene (BmSurvivin-2) from the silkworm, Bombyx mori

Xu-Dong TANG,Qiang Tu,Fei Mao,Xing-Rong Bai,Feng Zhu 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.4

The inhibitor of apoptosis proteins (IAP) plays an important role in maintaining the balance between cell proliferation and cell death. Here, we describe an IAP named BmSurvivin-2 isolated from tissues of Bombyx mori that contains only one baculoviral IAP repeat (BIR) domain and lacks a really interesting new gene (RING) finger domain. Cell viability and DNA fragment analysis showed that over-expression of BmSurvivin-2 could inhibit actinomycin D (ActD)-induced apoptosis in Sf9 cells, and its anti-apoptotic activity was dependent on its Nterminal BIR domain. Real-time PCR analyses indicated that BmSurvivin-2 mRNA was expressed in all tissues of silkworm and the highest expression level was found in testis and head. Expression of BmSurvivin-2 was found to gradually increase during the wandering stage of silkworm and decreased after wandering. Similar to deterin but not survivin, BmSurvivin-2 was primarily located in the cytoplasm. All these results provide insight into the role of a novel IAP in the silkworm, B. mori.

Effect of Nd Substitution for Mischmetal on Magnetic Properties in (MM,Nd)-Fe-B Ribbons

Zhu-bai Li,Jing-zhao Li,Zhi-yi Xu,Yong-feng Li,Xue-feng Zhang 한국자기학회 2020 Journal of Magnetics Vol.25 No.1

Mischmetal-based permanent magnets of (MM,Nd)12Fe82B6 were prepared by melt-spinning method via varying the relative content of mischmetal and Nd. The coercivity is low, and the squareness of hysteresis loop is poor in MM12Fe82B6 ribbons. The x-ray diffraction pattern, maximum of δm value as well as the temperature dependence of magnetization indicates that the partial substitution of Nd for MM could improve the crystallinity in the mischmetal-based magnets, and both the coercivity and squareness of hysteresis loop increase with Nd substitution for mischmetal. The increase of squareness should be partially attributed to the improvement in the crystallinity of R₂Fe14B crystal phase. For more than 4 at.% Nd substitution the coercivity is not less than that in corresponding (Ce,Nd)-based magnets, and the coercivity of 7.81 kOe and the maximum energy product of 15.41 MGOe were obtained in MM8Nd₄Fe82B6 ribbons. These investigations show that it is reasonable to use the low cost mischmetal to prepare the resource-saving rare-earth magnets, and that optimizing the addition amount of Nd is necessary to improve the crystallinity and enhance the magnetic properties.

MicroRNA-155 Expression has Prognostic Value in Patients with Non-small Cell Lung Cancer and Digestive System Carcinomas

Xu, Tong-Peng,Zhu, Can-Hong,Zhang, Jian,Xia, Rui,Wu, Feng-Lei,Han, Liang,Shen, Hua,Liu, Ling-Xiang,Shu, Yong-Qian Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Objective: Published data have shown that microRNAs (miRNAs) could play a potential role as diagnostic and prognostic indicators in cancers. Data for the predictive value of microRNA-155 are inconclusive. The aim of the present analysis was therefore to evaluate the role of miR-155 in prognosis for patients with a variety of carcinomas. Methods: Relevant studies were identified by searching PubMed and EMBASE. Data were extracted from studies comparing overall survival (OS), recurrence-free survival (RFS) or cancer-specific survival (CSS) in patients with carcinoma with higher miR-155 expression and those with lower levels. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) of miR-155 for clinical outcome were calculated. Results: A total of 15 studies were included. The pooled hazard ratio (HR) for OS of higher miR-155 expression in cancerous tissue was 1.89 (95% CI: 1.20-2.99, P=0.006), which could markedly predict poorer survival in general cancer. For RFS/CSS, elevated miR-155 was also associated with poor prognosis of cancer (HR=1.50, 95% CI: 1.10-2.05, P=0.01). On subgroup analysis, the pooled HR for OS in non-small cell lung cancer (NSCLC) was 2.09 (95% CI: 0.68-6.41, P > 0.05), but for RFS/CSS was 1.28 (95% CI: 1.05-1.55, P=0.015), with statistical significance; the pooled HRs for OS and RFS/CSS in digestive system neoplasms were 3.04 (95% CI: 1.48-6.24, P=0.003) and 2.61 (95% CI: 1.98-3.42, P<0.05), respectively. Conclusions: The results indicated that the miR-155 expression level plays a prognostic role in patients with cancer, especially NSCLCs and digestive system carcinomas.